Babies Listen and Learn While in the Womb

Jan. 3, 2013 -- Sometimes she just tells him about her day. Other times, Ruthie W. rubs her pregnant belly and tells her future son that she can’t wait to meet him (which should be any day now).

And a new study shows that he not only hears his mom, but may understand her and is already learning language from her.

“I talk to him all the time, even when I am in stores shopping for a layette and other things we will need once he is born,” says the New York City-based cosmetic executive. “People probably think I am crazy if they overhear me!”

The new research suggests that babies began to absorb language when they are inside the womb during the last 10 weeks of pregnancy -- which is earlier than previously held. Newborns can actually tell the difference between their mother’s native tongue and foreign languages just hours after they are born.

“The main message for new moms is that their babies are listening and learning and remembering during the last stages of pregnancy. Their brains do not wait for birth to start absorbing information,” says study author Patricia K. Kuhl, PhD. She is the Bezos Family Foundation endowed chair in early childhood learning and a professor of speech and hearing sciences at the University of Washington in Seattle.

How can researchers tell?

Kuhl and colleagues used a high-tech pacifier that was connected to a computer that measured infants' reactions to sounds. The study included 80 infants who were, on average, about 30 hours old and from Tacoma, Wash., and Stockholm, Sweden. They listened to vowel sounds in their native language and a foreign tongue while sucking on the pacifier.

Vowels are the loudest units in speech. The number of times they suck on the pacifier indicates which vowel sounds attracted their attention. Babies sucked longer for foreign languages than their native tongue in both countries, the study showed.

Building Blocks of Language

“The mother's voice can be heard because it is amplified by her body," Kuhl says.